Cycling 74 » Topic: Need camera advice from the installation gurus…

Need camera advice from the installation gurus…

stefantiedje — Wed, 16 Jun 2010 07:39:11 +0000

I am about to build an installation, which should track people moving to specific spots (6 alltogether). The room is not very high (less than 3 meters) and aproximately 8*10 meters in size. One camera from above would not see all spots. And of course our budget is very limited…
My plan is, to use multiple cameras placed at the ceiling. As we basically just want to trigger events, the resolution of the cameras can be low and black&white is fine as well. After some research I see two possibilities all with their own problems.

1. get 4 analog cameras and a box to combine them to a single video stream.
I found this: http://tinyurl.com/35a585g
and as cameras something like this: http://tinyurl.com/2ax9s5u
They have complete sets with adapters for the module which cost 20 Euros
This would be 180 Euros + cables.
Problem: I don’t know if I get that box recognized in Jitter on the Mac mini I plan to use. An additional video converter could be used as well, but would add to the cost…

2. get fire-i cameras and daisy chain them. This would be more than two times the price (a bit more than 100 Euros per camera), the cost for the cables would add on top and would eat too much of our budget. But it would be better usable for other projects…
Problem: I don’t know if a Mac mini is capable of handling 3 or 4 cameras at once for this kind of detection…

We would use a Mac mini for Max. One core would run the Jitter stuff, and the other core would run the audio (Its a sound installation, Jitter is only a detector…)

Are there other options I didn’t think of?
Which of the two is preferable considering the price difference…

Any advice is much appreciated…

Stefan

Re: Need camera advice from the installation gurus…

Jesse — Wed, 16 Jun 2010 21:23:45 +0000

Does it need to be a video solution? If you’re just detecting presence why not an arduino with six floor contact switches, or proimity sensors?

Re: Need camera advice from the installation gurus…

stefantiedje — Thu, 17 Jun 2010 13:15:35 +0000

I am open for anything, but there are advantages with the video soultion:
First, no cables at the spot, as the cameras would be at the ceiling. Second nothing to build, there is not too much time to do that…
I wonder if three cheap usb cams with long cables would work with a Mac mini or Macbook. Or would it eat too much processing power to decode three streams?

Stefan

Re: Need camera advice from the installation gurus…

Jesse — Thu, 17 Jun 2010 20:15:38 +0000

Hard to say about the performance – it would depend on the frame rate you need to capture all three cameras to get the timing resolution you require for detection.

The thing I would worry about with USB is the maximum cable length. You may end up needing to get a CAT5 extender or use a USB hub (repeater) if you go over 5m.

I’m also not entirely sure that Jitter will allow for multiple USB sources via jit.qt.grab – probably will, but you’d just have to try it out.

Re: Need camera advice from the installation gurus…

Floating Point — Thu, 17 Jun 2010 23:30:00 +0000

In my experience daisy chaining 2 fire-i is extremely unreliable. You will need to use a separate bus & port for each camera, which would (in most cases) require an extra firewire card. You are also limited by cable length (absolutely no more than 10m, preferably 3m or less).
T

Re: Need camera advice from the installation gurus…

stefantiedje — Wed, 30 Jun 2010 17:39:52 +0000

The soltion now is a quad mixer/digitizer with usb, and four analog cameras running on a cheap PC (dual core AMD processors). It works pretty well, the digitizer shows up in ji.dx.grab as Syntek STK1160…
But there is always a “but”
Maybe someone knows a solution: The only way to get the digitizer going, is to launch the program that is coming with it. Some sort of video surveillance primitive (its called “USB DVR Network”). As soon I once started it and close it immediately, I get the video signal into Jitter.
I guess that the drivers are not loading on its own. I have no idea how to do that without starting the program. There must be a way, but Windows certainly works different than a Mac and I know nothing about windows…

Any suggestion are well appreciated…

Stefan

Re: Need camera advice from the installation gurus…

painoff — Thu, 07 Oct 2010 20:27:59 +0000

Hi Stefan!
I got the same type of quad-video mixer, hoping to solve my multiple camera demands, but unfortunately i remained stuck in only 1-channel video input in jit.dx.grab. I have this MultiViewer program that reads all 4 cameras, but Max detects only 1 channel (and it is only my channel #2). I don’t know how was your adventure, but I would like to know if you had all 4 cameras inputs in jitter.
Thank you

Re: Need camera advice from the installation gurus…

ianc2674 — Sat, 09 Oct 2010 02:31:37 +0000

Another option, tho not one I’ve actually tried is to use an analog security camera switcher that does a quad analog composite camera display (4 live video screens on one) then feed that into a composite to firewire interface (like canopus). I have both of these items, but I;ve never tried using them together. One problem with mine is the security switcher has text overlays over the video that obscures some of the picture. But its analog, easy to switch on and would not burden the cpu of the mini. Not sure if they are readily available anymore as security stuff has gone all digital…

Re: Need camera advice from the installation gurus…

tobiasros — Tue, 01 May 2012 21:14:40 +0000

Hi, i have a similiar question:

I plan an installation with 3 live cameras (analog, pal), that will be outputted (and mixed with prerecorded sequences) on 9 screens. Each camera can appear on each screen over time.

I am considering the following setup:
3 computer with 3 monitor outputs each and also 3(or 4) grabbing inputs. The outputs are no problem, for the grabbing I was thinking of either a LFG4 or a spectra 8 for each computer (and a signal multiplier for each camera, that gives me 3 signals).

Alternatively a box that combines the 3 pal signals in one hd-stream, that can be captured with an hd-capture-device.

Has anybody on this list some experience with a similiar setup or recommendations for an reliable system?

Thanks, Tobias

Re: Need camera advice from the installation gurus…

ćwiek — Tue, 01 May 2012 21:24:36 +0000

i thing, that the most efficient and cheap way, to do it, is to get 4 ps3 eye cameras and special cl-eye paid drivers. than you will have to ask someone, to write you a software that stitch the videostreams (it would be easy with cl-eye drivers) and thats all. the advantages of this setup is 120 fps, and ease to modify for custom lenses and it is also cheap. the defects are that you have to buy long special cables or media hub and then transmit the signal over ethernet.

Re: Need camera advice from the installation gurus…

tobiasros — Tue, 01 May 2012 21:52:24 +0000

that sounds cool, but i have to use specific pan / tilt surveillance cameras for that installation…

Re: Need camera advice from the installation gurus…

ćwiek — Tue, 01 May 2012 22:32:28 +0000

servo? @:)

Re: Need camera advice from the installation gurus…

tobiasros — Tue, 01 May 2012 22:42:43 +0000

:-) also zoom and other adjustments… did it before directly connected to the monitors or 1 computer / grabber for each camera… but don’t want to use 9 computers…

https://vimeo.com/11564764

Re: Need camera advice from the installation gurus…

tobiasros — Wed, 09 May 2012 22:50:16 +0000

ok, small update: got a second-hand osprey 450e,and works wonderful with jit.dx.grab: grabbing 4 channel simultaneously with almost no latency. also there are chinese “clones” of the matrox tripleheadtogo which split to the dvi-outputs and have more choices for resolution…